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Three-Dimensional and Cross-sectional Characteristics of Normal Grain Growth Based on Monte Carlo Simulation 被引量:3
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作者 Xiaoyan Song Guoquan Liu(Material Science and Engineering School, University of Science and Technology Beijing, Beijing 100083, China)(Department of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1998年第3期129-133,139,共6页
An appropriate Monte Carlo method was developed to simulate the three-dimensional normal grain growth more completely. Comparative investigation on the three-dimensional and the cross-sectional characteristics of norm... An appropriate Monte Carlo method was developed to simulate the three-dimensional normal grain growth more completely. Comparative investigation on the three-dimensional and the cross-sectional characteristics of normal grain growth was done. It was found that the time exponent of grain growth determined from cross-section exhibits the same rule of increasing slowly with time and approaching the theoretical value n = 0.5 of steadygrain growth as the three-dimensional (3-D) system. From change of the number of grains per unit area with timemeasured in cross-section, the state of 3-D normal grain growth may be predicted. The gtain size distribution incross-section is different from that in 3-D system and can not express the evolution characteristic of the 3-D distribution. Furthermore, there exists statistical connection between the topological parameters in cross-section and thosein three-dimensions. 展开更多
关键词 Monte Carlo simulation normal grain growth THREE-DIMENSION cross-section CHARACTERISTICS
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Effect of mandrel on cross section quality of thin-walled tube numerical controlled bending 被引量:7
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作者 谷瑞杰 杨合 +2 位作者 詹梅 李恒 王光祥 《中国有色金属学会会刊:英文版》 EI CSCD 2005年第6期1264-1274,共11页
The effect of mandrel with the structure of ball and socket on the cross section quality of thin-walled tube numerical controlled(NC) bending was studied by numerical simulation method, combined with theoretical (anal... The effect of mandrel with the structure of ball and socket on the cross section quality of thin-walled tube numerical controlled(NC) bending was studied by numerical simulation method, combined with theoretical (analysis) and experiment. Influencing factors of the mandrel include the count of mandrel heads, the diameter of mandrel and its position. According to the principle of NC tube bending, quality defects possibly produced in thin-walled tube NC bending process were analyzed and two parameters were proposed in order to describe the cross section quality of thin-walled tube NC bending. According to the geometrical dimension of tube and dies, the range of mandrel protrusion was derived. The finite element model of thin-walled tube NC bending was established based on the DYNAFORM platform, and key technological problems were solved. The model was verified by experiment. The effect of the number of mandrel heads, the diameter of mandrel and the protrusion length of mandrel on the cross section quality of thin-walled tube NC bending was revealed and how to choose mandrel parameters was presented. 展开更多
关键词 芯棒 数控弯曲 薄壁管 横截面质量
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Effect of frictions on cross section quality of thin-walled tube NC bending 被引量:10
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作者 杨合 谷瑞杰 +1 位作者 詹梅 李恒 《中国有色金属学会会刊:英文版》 EI CSCD 2006年第4期878-886,共9页
The effect of frictions between dies and tube on the cross section quality of thin-walled tube numerical controlled(NC) bending was studied by numerical simulation method, combined with theoretical analysis and experi... The effect of frictions between dies and tube on the cross section quality of thin-walled tube numerical controlled(NC) bending was studied by numerical simulation method, combined with theoretical analysis and experiment. The results show that the frictions between mandrel, wiper, pressure die, bending die and tube have a significant and complicate effect on the section quality of thin-walled tube NC bending. To improve the section quality, frictions between mandrel, wiper and tube should be decreased, but the frictions between the pressure die, bending die and tube increase. The effect on the section distortion is more significant from mandrel, wiper, pressure die to bending die and the effect on the wall thinning more significant from mandrel, pressure die, wiper, to bending die. The effects of frictions between all dies and tube on wall thinning are smaller than their effects on section distortion. Mandrel and wiper should be lubricated well and drawing oil is used to lubricate them in actual production. The frictions between pressure die, bending die and tube should be increased and the dry friction is used between pressure die, bending die and tube in actual production. 展开更多
关键词 薄壁管 摩擦 横截面质量 弯曲挠度
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Microwave characteristic simulation research for a kind of novel electromagnetic structure
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作者 Xu Zhanxian Kong Lidu +1 位作者 Lin Weigan Jia Baofu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期467-472,共6页
A kind of novel electromagnetic structure of Cassini cross section is proposed and simulation is implemented with business microwave soft CST based on finite integral technique (FIT). The electromagnetic field mode ... A kind of novel electromagnetic structure of Cassini cross section is proposed and simulation is implemented with business microwave soft CST based on finite integral technique (FIT). The electromagnetic field mode type of Cassini wave-guide belongs to TE, and the electromagnetic field intensity is stronger near the neck region than at other areas. For Cassini electromagnetic patches and lumped elements, the radar cross section (RCS) is smaller around 7 GHz with -30.85 dBsm, and the absorbing property is better around 13 GHz with 4.56 dBsm difference of RCS from comparing of pure medium. For novel radiation structure of Cassini cross-section patches, the electromagnetic field value is larger in the neck areas of two half patches. At last, the potential application and development of Cassini oval structure are put forward in the electromagnetic stealth technology and antennae design. 展开更多
关键词 electromagnetic structure Cassini oval curves CST simulation MICROWAVE radar cross section.
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Monte Carlo simulation for pulsed neutron-neutron logging in fractured and cavernous carbonate formation
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作者 LIU Lipan MO Xiuwen +1 位作者 ZHANG Youshuo ZHANG Weifeng 《Global Geology》 2020年第1期32-37,共6页
The influence of carbonate formation on Pulsed Neutron logging(such as Pulsed Neutron-Neutron logging)is quite different from that of sandstone due to the complexity of reservoir architecture and the development of fr... The influence of carbonate formation on Pulsed Neutron logging(such as Pulsed Neutron-Neutron logging)is quite different from that of sandstone due to the complexity of reservoir architecture and the development of fracture in carbonate reservoir.To study the factors affecting Pulsed Neutron-Neutron(PNN)logging in carbonate formation,the responses on fracture or cave are simulated by Monte Carlo method,getting the relationships among the macroscopic capture cross section(Σ),the count ratio of the thermal neutron at far spacing and near spacing detectors(RATIO),the fracture porosity,oil-bearing and shale content of fracture.The results show that PNN logging can be used to detect caves,and there exist linear relationships among the macroscopic capture cross section(Σ),the count ratio(RATIO)and the above factors.The research findings in this paper provides theoretical basis for the interpretation and data correction of the PNN logging in carbonate reservoirs. 展开更多
关键词 carbonate formation PNN logging macroscopic capture cross section RATIO Monte Carlo simulation
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First principles simulation technique for characterizing single event effects 被引量:1
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作者 张科营 郭红霞 +5 位作者 罗尹虹 范如玉 陈伟 林东生 郭刚 闫逸华 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第6期524-529,共6页
This paper develops a new simulation technique to characterize single event effects on semiconductor devices. The technique used to calculate the single event effects is developed according to the physical interaction... This paper develops a new simulation technique to characterize single event effects on semiconductor devices. The technique used to calculate the single event effects is developed according to the physical interaction mechanism of a single event effect. An application of the first principles simulation technique is performed to predict the ground-test single event upset effect on field-programmable gate arrays based on 0.25μm advanced complementary metal-oxidesemiconductor technology. The agreement between the single event upset cross section accessed from a broad-beam heavy ion experiment and simulation shows that the simulation technique could be used to characterize the single event effects induced by heavy ions on a semiconductor device. 展开更多
关键词 single event effect static random access memory cross section simulation
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Simulation and Experiment on Workability for Cold Pressure Forming of Sheet Metal Part with Step Cross-section 被引量:3
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作者 LU Xianfeng LI Hufeng +1 位作者 ZHANG Yuerong ZHOU Yong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第2期161-165,共5页
In modem manufacturing, a new type of sheet metal part with step cross-section in both inner hole and outer edge is proposed. The traditional stamping separating processes can only produce sheet metal part with vertic... In modem manufacturing, a new type of sheet metal part with step cross-section in both inner hole and outer edge is proposed. The traditional stamping separating processes can only produce sheet metal part with vertical cross-section. According to the latest developing theory and potential of cold pressure forming: combination of pressure and cold forging, a new flow control forming of sheet metal(FCF) is excogitated based on blanking process of general stamping and combined with cold forging processes such as extrusion and coining, etc, which is aiming at the above-mentioned new type of sheet metal part. With utilization of this new process, the new type of sheet metal parts can be manufactured. In order to shorten the testing period, the numerical simulation was carried out by using DEFORM-3D software, and both deformation and mechanics rules were analyzed. Based on the simulation, both punching part and blanked parts of this new type were successfully developed. Then a new conception of optimal distance between the step walls of inner hole and outside edge was proposed and the design principle for its numerical value was inferred. Furthermore, a mold set for combination of stamping & cold forging was designed and manufactured, by which the technologic experiments were taken for validation with Aluminum plate of thickness 2.35 mm for power battery cover board, which verified the principle of the distance between the step walls. The research of cold pressure forming of thin sheet metal with step cross-section is significant, not only to the development of modem mechanical manufacture, but also to metal plastic forming science. 展开更多
关键词 sheet metal step cross-section numerical simulation distance between walls technologic experiment
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The quadratic B-spline curve fitting for the shape of log cross sections 被引量:2
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作者 任洪娥 吴妍 朱哓明 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期150-152,共3页
This paper describes a new method for simulation of the cross section shape of log. The self-developed MQK3102 log shape recognizing machine was used to acquire the finite discrete sampling points on the cross section... This paper describes a new method for simulation of the cross section shape of log. The self-developed MQK3102 log shape recognizing machine was used to acquire the finite discrete sampling points on the cross section of log and those points were fitted with the quadratic B-spline parametric curve. This method can clearly stimulate the real shape of the log cross section and is characterized by limited sampling points and high speed computing. The computed result of the previous curve does not affect the next one, which may avoid the graphic distortion caused by the accumulative error. The method can be used to simulate the whole body shape of log approximately by sampling the cross sections along the length direction of log, thus providing a reference model for optimum saw cutting of log. 展开更多
关键词 Quadratic B-spline curve cross section shape LOG Computer simulation Optimum saw cutting
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Simulation of Radar Cross Section of a Sort of Corrugated Screen
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作者 Fang Chong-hua 《中国舰船研究》 2008年第4期72-74,共3页
关键词 船舶工程 模拟技术 雷达 设计方案
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Ar^+/Ar, O_2^+/O_2 and N_2^+/N_2 Elastic Momentum Collision Cross Sections: Calculation and Validation Using the Semi-Classical Model
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作者 Djilali BENYOUCEF Mohammed YOUSFI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2014年第6期588-592,共5页
The aim of this paper is to obtain relevant sets of collision cross sections of the parent ions in low pressure discharges in argon, oxygen, and nitrogen, i.e., Ar+ in Ar, O2+ in O2 and N2+ in N2. These ion data ar... The aim of this paper is to obtain relevant sets of collision cross sections of the parent ions in low pressure discharges in argon, oxygen, and nitrogen, i.e., Ar+ in Ar, O2+ in O2 and N2+ in N2. These ion data are first discussed and then validated from comparisons between the calculated transport coefficients and those measured in the literature. The elastic momentum transfer collision cross sections are determined from a semi-classical approximation for the phase shift calculation based on a 12-6-4 inter-particle potential while ion transport coefficients are determined versus the reduced electric field from Monte Carlo simulations. 展开更多
关键词 inter-particle interaction potentials phase shift JWKB (Jeffreys WentzelKramers Brillouin) momentum collision cross sections Monte Carlo simulation ion trans-port coefficient
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Optimization of structural parameters for elliptical cross-section spiral equal-channel extrusion dies based on grey theory 被引量:2
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作者 Wang Chengpeng Li Fuguo +2 位作者 Lu Hongya Yuan Zhanwei Chen Bo 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第1期209-216,共8页
The elliptical cross-section spiral equal-channel extrusion (ECSEE) process is simulated by using Deform-3D finite element software. The ratio m of major-axis to minor-axis length for ellipse-cross-section, the tors... The elliptical cross-section spiral equal-channel extrusion (ECSEE) process is simulated by using Deform-3D finite element software. The ratio m of major-axis to minor-axis length for ellipse-cross-section, the torsion angle u, the round-ellipse cross-section transitional channel L1, the elliptical rotation cross-section transitional channel L2 and the ellipse-round cross-section transitional channel L3 are destined for the extrusion process parameters. The average effective strain eave on cross-section of blank, the deformation uniformity coefficient a and the value of maximum damage dmax are chosen to be the optimize indexes, and the virtual orthogonal experiment of L16 (45) is designed. The correlation degree of the process factors affecting eave, a and dmax is analyzed by the numerical simulation results using the weights and grey association model. The process parameters are optimized by introducing the grey situation decision theory and the ECSEE optimal combination of process parameters is obtained: u of 120 , m of 1.55, L1 of 7 mm, L2 of 10 mm, and L3 of 10 mm. Simulation and experimental results show that the material can be refined with the optimized structural parameters of die. Therefore, the optimization results are satisfactory. 展开更多
关键词 Correlation degree Elliptical cross-section spiral equal-channel extrusion (ECSEE) Grey theory OPTIMIZATION Orthogonal design simulation
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Frailty,multimorbidity and quality of life in an ageing population in Africa:a cross-sectional,population-based study in rural and urban Rwanda
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作者 Michael Boah Callixte Cyuzuzo +6 位作者 Francois Uwinkindi Chester Kalinda Tsion Yohannes Carolyn Greig Justine Davies Lisa R Hirschhorn Alemayehu Amberbir 《Family Medicine and Community Health》 2025年第4期79-87,共9页
Objective As populations age,multimorbidity and frailty have emerged as major health challenges.While their associations with disability and mortality are well documented,their impact on quality of life(QoL)in sub-Sah... Objective As populations age,multimorbidity and frailty have emerged as major health challenges.While their associations with disability and mortality are well documented,their impact on quality of life(QoL)in sub-Saharan Africa remains underexplored.We examined the associations between frailty,multimorbidity and QoL among older adults in Rwanda.Design A cross-sectional population-based study.Multimorbidity was defined as having two or more chronic conditions,including hypertension,diabetes,heart disease and mental health conditions.Frailty scores were derived using the Fried phenotype,and QoL was measured using the European Health Instrument Survey-Quality of Life index(scaled 0%–100%).Sequential linear regression models were used to examine independent associations.Setting Rural and urban settings of Rwanda.Participant We analysed data from 4369 adults(≥40 years).Results The mean QoL score was 48.2%(±15.6).Frailty and multimorbidity prevalence were 14.5%(95%CI 13.5 to 15.6)and 55.2%(95%CI 53.7 to 56.6),respectively,while 55.0%(95%CI 53.3 to 56.3)were classified as prefrail.Frailty and multimorbidity are independently associated with poorer QoL.Compared with robust individuals,prefrail and frail individuals experienced a 3.66(95%CI−4.63 to–2.70)and 7.30(95%CI−8.76 to–5.83)percentage point reduction in QoL,respectively.Multimorbidity was associated with a 4.66%(95%CI−5.54 to–3.79)point decrease in QoL.Impairments in activities of daily living partly mediated these associations.Conclusions Frailty and multimorbidity showed a strong negative association with QoL,with frailty having a stronger effect.These findings underscore the need for age-responsive healthcare strategies,including frailty screening and integrated chronic care,to enhance QoL among older adults in Rwanda. 展开更多
关键词 quality life qol quality life frailty cross sectional study sub saharan africa population based study multimorbidity rural urban settings
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复杂异形截面环件径向轧制孔型填充快速模拟
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作者 周黎 兰箭 郑继荣 《塑性工程学报》 北大核心 2026年第1期79-85,共7页
为保证复杂异形截面环件直径达到预计目标尺寸时其孔型填充情况同时符合实际工艺要求,建立了一种环件二维轴对称多步胀形有限元模型,综合运用二维上限元法与二维有限元方法提出了等效矩形截面环件的计算方法,并利用二维上限元法计算等... 为保证复杂异形截面环件直径达到预计目标尺寸时其孔型填充情况同时符合实际工艺要求,建立了一种环件二维轴对称多步胀形有限元模型,综合运用二维上限元法与二维有限元方法提出了等效矩形截面环件的计算方法,并利用二维上限元法计算等效矩形截面环件胀形过程速度场,然后通过二维轴对称有限元软件求解当前胀形步环件孔型填充情况。以钛合金机匣环件为例,采用二维轴对称有限元软件求解时间只需5~15 min,与三维有限元环件轧制模拟结果相比,环件截面填充率和内外径尺寸精度误差均在10%以内。通过环件二维轴对称多步胀形有限元模拟计算,可大幅减少环件轧制工艺设计与优化时间,提高生产效率。 展开更多
关键词 复杂异形截面环件 快速模拟 二维轴对称 有限元模拟
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黄河流域甘肃段水资源承载力动态特征研究
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作者 王丽宁 杜森 +2 位作者 王嘉鑫 胥德泽 孙佛佑 《国土与自然资源研究》 2026年第1期83-87,共5页
科学合理测度黄河流域甘肃段水资源承载力及水资源供需平衡状况可以为黄河流域甘肃段高质量发展提供理论参考与决策依据。本研究基于系统动力学方法(System Dynamics,SD),结合水资源、城镇公共、农业、生活、产业、生态6个子系统,构建... 科学合理测度黄河流域甘肃段水资源承载力及水资源供需平衡状况可以为黄河流域甘肃段高质量发展提供理论参考与决策依据。本研究基于系统动力学方法(System Dynamics,SD),结合水资源、城镇公共、农业、生活、产业、生态6个子系统,构建黄河流域甘肃段水资源承载力定量评估SD模型,动态模拟不同发展情景下2023-2035年区域水资源承载力及供需变化。结果表明,自然增长模式下2035年黄河流域甘肃段总需水量为64.0687亿m3,高质量发展模式下2035年总需水量为61.4890亿m3;自然增长模式下黄河流域甘肃段2035年水资源承载限制系数为1.43,高质量发展模式下为1.35,相较自然增长模式,高质量发展模式下的黄河流域甘肃段水资源承载力较好。研究成果可以为黄河流域甘肃段水资源的高效合理利用提供理论支撑。 展开更多
关键词 水资源承载力 黄河流域甘肃段 SD 情景模拟 高质量发展
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Deductive Fault Simulation Algorithm Based on Fault Collapsing
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作者 宫云战 魏道政 《Journal of Computer Science & Technology》 SCIE EI CSCD 1993年第2期182-187,共6页
The true value simulation is necessary in the critical path tracing fault simulation algorithm.The critical and non-critical inputs can be known after the number of controlling and non-controlling inputs and the criti... The true value simulation is necessary in the critical path tracing fault simulation algorithm.The critical and non-critical inputs can be known after the number of controlling and non-controlling inputs and the criticality of output of every gate are determined.Single output region(SOR)is defined for non-critical lines,so many other non-critical lines can be obtained before fault simulation.Then deductive fault simulation algorithm is used to compute the fault list for every possible critical line from bottom to top,which can greatly decrease the length of fault list and simulation time.The cross-section is defined to reduce the storage space.The experimental results are given at the end of the paper. 展开更多
关键词 Fault simulation cross-section single output region
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不同断面形式对干渠输水效率的规划影响分析
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作者 徐沛力 徐伟 +1 位作者 张科浩 范晓泉 《价值工程》 2026年第3期19-21,共3页
为了提升干渠输水效率,以南水北调中线干渠为例,分析了不同断面形式对输水结构、水流稳定性及能耗的综合影响。数值模拟显示,U形断面平均流速达1.12m/s,单位能耗最低为2.97J/m^(3),水头损失梯度为22.7m/km,稳定性最优;矩形断面施工适应... 为了提升干渠输水效率,以南水北调中线干渠为例,分析了不同断面形式对输水结构、水流稳定性及能耗的综合影响。数值模拟显示,U形断面平均流速达1.12m/s,单位能耗最低为2.97J/m^(3),水头损失梯度为22.7m/km,稳定性最优;矩形断面施工适应性强,能耗为3.42J/m^(3);梯形断面虽断面面积大但紊动强度高达0.036m^(2)/s^(2),能耗波动剧烈。结构边界形态主导水力效率变化。 展开更多
关键词 干渠输水 断面形式 数值模拟
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Relationship of Lifestyle Habits with Sleep Quality among Japanese in Their 20s
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作者 Tomohide Yagyu Kohei Akazawa +4 位作者 Minami Ebihara Junta Ishikawa Koichi Ouchi Koji Kobayashi Kyoko Nakazawa 《Health》 2019年第1期1-8,共8页
The purpose of this study was to analyze the effects of lifestyle on sleep quality in young Japanese adults. A cross-sectional study was conducted on the web. We analyzed 637 eligible subjects (316 men and 321 women) ... The purpose of this study was to analyze the effects of lifestyle on sleep quality in young Japanese adults. A cross-sectional study was conducted on the web. We analyzed 637 eligible subjects (316 men and 321 women) aged 20 - 29 years. Information on diet and individual lifestyle characteristics, including sleep quality, which was assessed using the Pittsburgh Sleep Quality Index Japanese version (PSQI-J). Results were obtained by participants completing an online questionnaire. The participants were divided into two groups based on whether they were students (“student group”) or not (“not student group”). The participants with a PSQI-J global score of 6 or higher were evaluated as low-sleep-quality. Logistic regression analyses were performed to evaluate associations of lifestyle habits with low-sleep-quality. Logistic regression analyses were applied for “student group” and “not student group”. The results showed that days of eating out at dinner (OR: 1.11, CI: 1.00 - 1.22) and skipping dinner (OR: 1.21, CI: 1.05 - 1.42) were significant and independent predictors for low-sleep-quality among the “not student group”. There were no significant and independent predictors for low-sleep-quality among “student group”. Our results suggested that excessive intake by eating out and deficient intake by skipping dinner might lead to a high PSQI-J score. It is necessary for young people to receive education on the importance of cooking their own meals for traditional and daytime eating. The implication of this study lies in the fact that we have analyzed the effects of lifestyle habits on quality of sleep. 展开更多
关键词 SLEEP quality EATING Out SKIPPING MEAL cross-sectionAL Study Pittsburgh SLEEP quality Index
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Effect of Eating out on Quality and Quantity of Sleep among Japanese in Their 20s
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作者 Tomohide Yagyu Kohei Akazawa +2 位作者 Minami Ebihara Junta Ishikawa Ouchi Koichi 《Health》 2018年第9期1261-1269,共9页
The purpose of this study was to analyze the effects of eating out or skipping meals on the quality or quantity of sleep in young Japanese adults. We analyzed 584 eligible subjects (283 men and 301 women) aged 20 - 29... The purpose of this study was to analyze the effects of eating out or skipping meals on the quality or quantity of sleep in young Japanese adults. We analyzed 584 eligible subjects (283 men and 301 women) aged 20 - 29 years. Information on diet and individual lifestyle characteristics, including sleep quality, which was assessed by the Pittsburgh Sleep Quality Index Japanese version (PSQI-J), were obtained by participants completing an online questionnaire. Kendall’s tau coefficient was used to measure the ordinal association between diet and sleep quality. The Mann-Whitney U test was performed to evaluate differences in sleep quality by frequency of eating out and frequency of skipping meals. The results revealed a significant difference in sleep duration and PSQI-J score between people who eat out >2 times a week (“high restaurants group”) and those who do not (“low restaurants group”). Furthermore, whereas the mean sleep duration in the “high restaurants group” was 6.59 hours, the mean sleep duration in the “low restaurants group” was 6.90 hours (p = 0.007). The PSQI-J score was significantly higher in the “high restaurants group” than in the “low restaurants group” (4.91 versus 4.37, p = 0.006). Significant differences were also evident in the test’s component scores: C2, C3, and C7. No significant difference was found in sleep duration and PSQI-J score between the groups in terms of frequency of skipping meals (breakfast, lunch, and dinner). Our results suggested that excessive intake by eating out more than twice a week may lead to short sleep duration and high PSQI-J score. 展开更多
关键词 SLEEP quality Dietary HABITS cross-sectionAL Study Pittsburgh SLEEP quality Index EATING OUT
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北京市31家三级甲等医院急诊科静脉血管通路使用及管理的现况调查
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作者 宋莉莉 彭可 +2 位作者 鲁寒 茹鸿 王蕾 《中国护理管理》 北大核心 2025年第11期1698-1702,共5页
目的:调查北京市三级甲等医院急诊科静脉血管通路的使用及管理现状,并分析当前存在的问题,为推动静脉治疗的专业化、规范化管理提供依据。方法:采用便利抽样法,于2024年11月选取北京市31家三级甲等医院急诊科护理管理者或静脉治疗团队... 目的:调查北京市三级甲等医院急诊科静脉血管通路的使用及管理现状,并分析当前存在的问题,为推动静脉治疗的专业化、规范化管理提供依据。方法:采用便利抽样法,于2024年11月选取北京市31家三级甲等医院急诊科护理管理者或静脉治疗团队负责人进行问卷调查。问卷内容包括急诊科一般资料,静脉血管通路的使用、评估与选择及管理情况。结果:31家医院急诊科均使用外周静脉留置针,14家仍会使用一次性静脉输液钢针,19家使用可视化技术进行静脉通路留置;25家急诊科会评估患者对输液工具的选择偏好,16家在输注血管活性药物时会选择静脉留置针;24家医院急诊科有静脉治疗质量评价标准,4家医院急诊科有静脉治疗信息管理系统。结论:急诊科静脉治疗工具多样,静脉血管通路评估较为全面,但需要加强对血管活性药物静脉治疗的规范。 展开更多
关键词 急诊科 静脉血管通路 质量管理 横断面研究
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悬浮隧道截面形状与系泊方式对抗冲击能力影响
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作者 徐万海 沙沐 +1 位作者 李明鎏 李航 《哈尔滨工程大学学报》 北大核心 2025年第7期1268-1278,共11页
水中悬浮隧道遭受突发撞击时,管体强度变化、系统可靠性以及结构动力响应十分复杂,针对悬浮隧道受到撞击后能否继续安全运营的不确定性,应用有限元对悬浮隧道损伤与运动响应进行模拟是一种非常有效的方法。本文采用ABAQUS开展了撞击作... 水中悬浮隧道遭受突发撞击时,管体强度变化、系统可靠性以及结构动力响应十分复杂,针对悬浮隧道受到撞击后能否继续安全运营的不确定性,应用有限元对悬浮隧道损伤与运动响应进行模拟是一种非常有效的方法。本文采用ABAQUS开展了撞击作用下悬浮隧道响应数值分析,构建了有限元模型;确定了模型材料及各部分单元类型;提出了管节接头的处理方式,探究了不同悬浮隧道截面形状及锚索布置方式对结构灾变的影响机制。研究结果表明:四边形截面隧道管体受撞击后管体的位移和损伤最小,是抵抗冲击最佳的形式。锚索布置方式不会影响悬浮隧道的撞击应力、应变及损伤,仅影响悬浮隧道的运动响应,其中两垂直两倾斜的系泊方式可显著限制悬浮隧道的撞击运动幅度。 展开更多
关键词 水中悬浮隧道 撞击载荷 锚索布置方式 截面形状 数值模拟 动力响应 结构损伤 应力分析
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